A case of myxoedema coma successfully treated by low dose oral triiodothyronine.

Myxoedema coma is fortunately rare and is probably rarer in a warm climate such as Australia. It carries a high mortality rate. Its correct management is still a controversial issue. A case of severe myxoedema coma who was successfully treated is described. Thyroid hormone was replaced in the form of triiodothyronine given orally in doses of 20-40 microng/day. There was an improvement in body temperature within six hours of the first dose; this was accompanied by a brisk fall in serum CPK and cholesterol with a rapid rise of plasma T3 into the euthyroid range. There was a defect in water excretion which was rapidly reversed as renal function returned to normal. Review of the literature suggests that low dose oral therapy with T3 is a satisfactory form of initial management.